Non-Obstetric Maternal Mortality Trends by Race in the United States

Public health interventions to reduce maternal mortality have largely focused on obstetric causes of death. However, previous studies have noted that non-obstetrics factors, such as motor vehicle accidents, substance overdoses, homicides, and suicides, may account for a large proportion of maternal deaths. The study objective was to examine trends in maternal deaths from non-obstetric causes across races in the United States (US).

A population-based cross-sectional study was conducted on 80,710,348 live births using data from the "Birth Data" and "Mortality Multiple Cause" files compiled by the Centers for Disease Control and Prevention from 2000 to 2019. The annual incidence of maternal deaths attributed to non-obstetric causes (/100,000 live-births) during pregnancy and up to 42 days postpartum were calculated across racial groups. Then the effects of race on the risk of non-obstetric maternal mortality and temporal changes over the study period were examined using logistic regression models.

From 2000 to 2019, a total 7,334 women died during pregnancy, childbirth, and within 42 days postpartum from non-obstetric causes, representing 34.5% (7,334/21,241) of all maternal mortality. Of non-obstetric deaths, 31.3% were caused by transport accidents and 27.3% by accidental poisoning. American Indian women were found to have the highest risk of non-obstetric maternal mortality (OR 2.20,95% CI 1.90-2.56), and 46.1% (176/382) of all deaths among pregnant American Indian women were caused by non-obstetric complications. Risk of non-obstetric maternal mortality increased overall during the 20-year study period, with a greater increase among Black (1.15, 1.13-1.17) and American Indian women (1.17, 1.13-1.21).

Non-obstetric causes of death have become increasingly prevalent in the US, especially in American Indian women. Novel interventions to address these non-obstetric factors should especially target American Indian women to improve maternal outcomes.